The effect of forced recall on illusory recollection in younger and older adults

The effect of an initial forced recall test on later recall and recognition tests was examined in younger and older adults. Subjects were presented with categorized word lists and given an initial test under standard cued recall instructions (with a warning against guessing) or forced recall instructions (that required guessing); subjects were later given a cued recall test for the original list items. In 2 experiments, initial forced recall resulted in higher levels of illusory memories on subsequent tests (relative to initial cued recall), especially for older adults. Older adults were more likely to say they remembered rather than knew that forced guesses had occurred in the original study episode. The effect persisted despite a strong warning against making errors in Experiment 2. When a source monitoring test was given, older adults had more difficulty than younger adults in identifying the source of items they had originally produced as guesses. If conditions encourage subjects to guess on a first memory test, they are likely to recollect these guesses as actual memories on later tests. This effect is exaggerated in older adults, probably because of their greater source monitoring difficulties. Both dual process and source monitoring theories provide insight into these findings.     

Can intentional forgetting reduce false memory? Effects of list-level and item-level forgetting

This study examined whether false memory produced by the learning of lists of categorized and associative materials could be reduced by directed forgetting. The number of items within a list that participants were asked to remember or forget was manipulated, while the length of the list remained constant. Experiment 1a used categorized lists and Experiment 1b used associative lists; the participants performed immediate free recall and cued recall tests. For both the categorized and associative lists, the rate of false recall increased upon increasing the proportion of "forget" (F) words. After removing the immediate recall test, Experiment 2 found that intentionally forgetting part of the studied list reduced false memory, whereas forgetting the whole studied list did not. The results are discussed in terms of the list-level-vs.-item-level inhibition in semantic activation and the role of monitoring in reducing false memory.     

定向遗忘中提取抑制的机制：成功提取引起抑制

两个实验采用无关材料考察了字表方式下提取诱发遗忘解释定向遗忘中提取抑制的可能性。在实验中,学习完两个字表后,对字表2 进行不同次数（0、1、3次）的提取练习以考察是否会增强定向遗忘效应以及定向遗忘效应是否随着提取练习次数的增加而增强。实验一中,字表2提取练习是要求被试回忆字表2项目,不给予线索提示。在实验二中,采用词干补笔测验的形式对字表2进行提取练习,词干补笔测验保证了对字表2项目的成功提取。研究结果发现,只有在实验二中对字表2的成功提取练习增强了定向遗忘效应,从而表明成功提取可以解释定向遗忘中的提取抑制     

Repetition effects in directed forgetting: evidence for retrieval inhibition

Four experiments were conducted in support of a role for memory retrieval inhibition in directed forgetting. In each experiment, subjects were presented a list of words, some of which they were instructed to remember and some of which they were instructed to forget. After a recall test for all the words, the list was repeated. This time, however, all the words were presented with instructions that they be remembered. The improvement in recall from Trial 1 to Trial 2 was greater for the “forget” (F) words than for the “remember” (R) words. This difference was not due to a memorization-difficulty, item-selection effect (Experiment 2), a differential priority for rehearsal or output position given to the F items on Trial 2 (Experiment 3), or the greater number of F items left to be learned after Trial 1 (Experiment 4). Thus, the differential improvement from List 1 to List 2 for the F items was interpreted as a release of retrieval inhibition owing to the change in cue from forget to remember.     

Directed forgetting of emotional stimuli in borderline personality disorder

On the basis of clinical literature, the authors hypothesized that individuals with borderline personality disorder (BPD) would show biased information processing when they were exposed to negative affective stimuli of a particular type. Individuals with BPD and controls were tested using a directed forgetting paradigm. Study participants were exposed to 3 types of words (borderline, neutral, positive) and were cued to either remember or forget each word as it was presented. There were no group differences on a free recall task for words in the remember condition. However, participants with BPD recalled significantly more of the borderline words from the forget condition than did controls. In other words, borderline participants remembered borderline words that they were instructed to forget. These results may be consistent with enhanced encoding of salient words and perhaps related themes in BPD individuals.     

Familiarity is related to conceptual implicit memory: An examination of individual differences

Explicit memory is thought to be distinct from implicit memory. However, growing evidence has indicated that explicit familiarity-based recognition memory judgments rely on the same process that supports conceptual implicit memory. We tested this hypothesis by examining individual differences using a paradigm wherein we measured both familiarity and conceptual implicit memory within the same participants. In Experiments 1a and 1b, we examined recognition memory confidence ROCs and remember/know responses, respectively, to estimate recollection and familiarity, and used a free association task to measure conceptual implicit memory. The results demonstrated that, across participants, familiarity, but not recollection, was significantly correlated with conceptual priming. In contrast, in Experiment 2, utilizing a similar paradigm, a comparison of recognition memory ROCs and explicit associative cued-recall performance indicated that cued recall was related to both recollection and familiarity. These results are consistent with models assuming that familiarity-based recognition and conceptual implicit memory rely on similar underlying processes.     

Directed forgetting of autobiographical events

Two diary experiments demonstrated directed forgetting (DF) of autobiographical events, previously observed only for less complex memory items. Using a 2-week diary paradigm, we compared recall between a group of participants who were directed to forget Week 1 memories (forget group) and a group who did not receive a forget instruction (remember group). In Experiment 1, the forget group remembered fewer items from Week 1 than did the remember group. The effect was observed for negative and positive valence events, as well as for high and low emotional intensity events. The effect was replicated in Experiment 2 despite a memorable holiday (Valentine's Day) that occurred during the manipulation week. Forget participants remembered fewer low emotional intensity items in Experiment 2. We conclude that intentional forgetting is a plausible explanation for the loss of some autobiographical memories.     

Memory for previous recall: a comparison of free and cued recall

Case studies of individuals who claimed to have recovered previously repressed memories of abuse during situations that involved memory cueing revealed that some individuals had discussed abuse with others during an earlier time period. Termed the ‘forgot‐it‐all‐along’ effect, this phenomenon has legal implications for statutes of limitations. Two experiments provide evidence for differences between free recall and more directed (recognition or cued recall) test conditions in the accuracy of memories for previous recall. Participants more often erred by claiming they had not previously remembered recognized (Experiment 1) or cued (Experiment 2) sentences than freely recalled sentences, and this difference was obtained even when the number of remembered sentences was equivalent across conditions (Experiment 2). These studies document that memory for previous recollection is less accurate for cued memories even when remembered events do not produce feelings of shock or surprise. Copyright © 2002 John Wiley & Sons, Ltd.     

Cognitive load hypothesis of item-method directed forgetting

This study examined the effect of the processing demands of to-be-remembered (TBR) words on item-method directed forgetting. Experiment 1 found that a standard memory group remembered fewer to-be-forgotten (TBF) words than a naming group, in which participants simply named the TBR words during the study phase, even though both groups were equally instructed to forget the TBF words. Experiment 2 manipulated the number of TBR words in the study list, keeping the number of TBF words constant, and found that TBF word forgetting was more difficult in the few TBR words condition than the more TBR words condition. The same pattern was found in the result of Experiment 3 when a cued recall test, instead of a free recall test, was used. In all the experiments, participants were asked to recall the TBF words before the TBR words. These findings are consistent with the cognitive load hypothesis that it is easier to forget when there are fewer cognitive resources available during encoding.     

Cognitive load hypothesis of item-method directed forgetting

This study examined the effect of the processing demands of to-be-remembered (TBR) words on item-method directed forgetting. Experiment 1 found that a standard memory group remembered fewer to-be-forgotten (TBF) words than a naming group, in which participants simply named the TBR words during the study phase, even though both groups were equally instructed to forget the TBF words. Experiment 2 manipulated the number of TBR words in the study list, keeping the number of TBF words constant, and found that TBF word forgetting was more difficult in the few TBR words condition than the more TBR words condition. The same pattern was found in the result of Experiment 3 when a cued recall test, instead of a free recall test, was used. In all the experiments, participants were asked to recall the TBF words before the TBR words. These findings are consistent with the cognitive load hypothesis that it is easier to forget when there are fewer cognitive resources available during encoding.     

Musical stem completion: humming that note

This study looked at how people store and retrieve tonal music explicitly and implicitly using a production task. Participants completed an implicit task (tune stem completion) followed by an explicit task (cued recall). The tasks were identical except for the instructions at test time. They listened to tunes and were then presented with tune stems from previously heard tunes and novel tunes. For the implicit task, they were asked to sing a note they thought would come next musically. For the explicit task, they were asked to sing the note they remembered as coming next. Experiment 1 found that people correctly completed significantly more old stems than new stems. Experiment 2 investigated the characteristics of music that fuel retrieval by varying a surface feature of the tune (same timbre or different timbre) from study to test and the encoding task (semantic or nonsemantic). Although we did not find that implicit and explicit memory for music were significantly dissociated for levels of processing, we did find that surface features of music affect semanticjudgments and subsequent explicit retrieval.     

Can survival processing enhance story memory? Testing the generalizability of the adaptive memory framework

Research from the adaptive memory framework shows that thinking about words in terms of their survival value in an incidental learning task enhances their free recall relative to other semantic encoding strategies and intentional learning (Nairne, Pandeirada, & Thompson, 2008). We found similar results. When participants used incidental survival encoding for a list of words (e.g., "Will this object enhance my survival if I were stranded in the grasslands of a foreign land?"), they produced better free recall on a surprise test than did participants who intentionally tried to remember those words (Experiment 1). We also found this survival processing advantage when the words were presented within the context of a survival or neutral story (Experiment 2). However, this advantage did not extent to memory for a story's factual content, regardless of whether the participants were tested by cued recall (Experiment 3) or free recall (Experiments 4-5). Listening to a story for understanding under intentional or incidental learning conditions was just as good as survival processing for remembering story content. The functionalist approach to thinking about memory as an evolutionary adaptation designed to solve reproductive fitness problems provides a different theoretical framework for research, but it is not yet clear if survival processing has general applicability or is effective only for processing discrete stimuli in terms of fitness-relevant scenarios from our past.     

The effects of cueing and constraint instructions on children's free recall performance

The performance of nursery school children was investigated in two experiments involving cued and constrained free recall. Under constrained instructions, subjects were required to recall items by category. Under cued instructions subjects could recall items in any order they wished but the organized nature of the lists was identified and subjects were told that they would remember more if they recalled things from the same category together. No effects of cueing instructions were obtained in either Experiment I or Experiment II. Constrained recall instructions led to enhanced recall and category clustering. However, the beneficial effects were not maintained on later trials with the same list or on a transfer list when the constraints on recall were dropped. In addition, the introduction of constrained recall instructions had identical effects whether they were introduced early or late in practice. The results were discussed in terms of the influences of variables which affect the subjects' use of retrieval strategies and the development of memory.     

Release from generation failure: The role of study list structure

Three experiments, using the original encoding-specificity paradigm, investigated the role of study list structure in producing Higham and Tam's (2005) generation failure effect. Generation failure occurs when cued recall performance for strong, extralist cues is worse than target production in a control group that is given no study list but is instead required merely to generate responses to the same test cues. In the present study, generation failure was replicated in Experiment 1, and Experiment 2 demonstrated that strong, extralist cues were more likely to elicit targets in pure generation groups when participants had studied a list of strong associates than when they had studied a list of weak ones. In Experiment 3, participants were released from generation failure when a study list of moderate associates was used and the cue-to-target associative strength was equated between the reinstated- and extralist-cue conditions. Together, these results suggest that generation failure is partly attributable to participants' searching inappropriate domains that, though consistent with the study list structure, are unlikely to contain targets.     

Recall and stem-completion priming have different electrophysiological correlates and are modified differentially by directed forgetting

The notion that different aspects of memory are assessed by explicit and implicit memory tests was supported by behavioral and electrophysiological results. In a study-test procedure, 24 subjects were instructed to remember some words and to forget other words. Free recall and cued recall were better for words associated with the remember instruction, whereas directed forgetting did not influence stem completion (an implicit memory test). Event-related brain potentials elicited during study differed as a function of subsequent memory performance for free recall and cued recall, but not for stem completion. These results implicate encoding differences in the distinction between the 2 types of memory test. Factors governing whether explicit retrieval affects performance on an implicit memory test, mechanisms that may underlie directed-forgetting effects, and the importance of electrophysiological correlates of memory are also discussed.     

Intention superiority effect on implicit memory of shopping lists: Activation and inhibition processes

Intentional memory is defined as the ability to remember to perform intentions in the future. Forming an intention such as “shopping” activates access to memories related to the products on the shopping list. As Intention Superiority Effect (ISE) studies show, these memories are more accessible in semantic and episodic memory, more activated over time and protected from competing representations. The inhibition of competing representations in intentional memory has been little examined so far. In this study we attempt to analyze changes in activation in the recall of products on a shopping list and competitors through implicit memory tasks. Sixty-five participants learned two shopping lists on a computer. Later, they were told to virtually buy one of them (prospective list) and not the other (neutral list). Prior to intentional task execution, they performed an implicit retrieval task in which we manipulated the appearance or not of cues from the intentional list and analyzed the influence of the items from the intentional list on items related to intentional and neutral lists. The main result of this study is that intention retrieval by intentional cues strengthens the activation of products related to the intentional list and/or inhibits competing products related to the neutral list. The inhibition is episodic rather than semantic in nature. The ISE requires the recall of the intention during the retention period through intentional cues for maintaining the intention. This seems to defend automatic recovery theories and not the intention persistence hypothesis. Also, the results are better explained by the directed forgetting paradigm rather than by the retrieval-induced forgetting paradigm.     

I owe you: age-related similarities and differences in associative memory for gains and losses

Older adults often experience associative memory impairments but can sometimes remember important information. The current experiments investigate potential age-related similarities and differences associate memory for gains and losses. Younger and older participants were presented with faces and associated dollar amounts, which indicated how much money the person “owed” the participant, and were later given a cued recall test for the dollar amount. Experiment 1 examined face-dollar amount pairs while Experiment 2 included negative dollar amounts to examine both gains and losses. While younger adults recalled more information relative to older adults, both groups were more accurate in recalling the correct value associated with high-value faces compared to lower-value faces and remembered gist-information about the values. However, negative values (losses) did not have a strong impact on recall among older adults versus younger adults, illustrating important associative memory differences between younger and older adults.     

Intentional forgetting can increase,not decrease,residual influences of to-be-forgotten information

Intentionally forgotten information remains in memory at essentially full strength, as measured by recognition and priming, but access to that information is impaired, as measured by recall. Given that pattern, it seemed plausible that intentionally forgotten information might have a greater impact on certain subsequent judgments than would intentionally remembered information. In 2 experiments, participants cued to forget nonfamous names were subsequently more likely to make false attributions of fame to those names than were participants instructed to remember them. These findings implicate retrieval inhibition as a potent factor in the interplay of recollection and priming in memory and judgment. They also point to possible unintended consequences of instructions to forget, suppress, or disregard in legal or social settings.     

Remembrance of remembrance past

Arnold and Lindsay (2002) found that individuals more often failed to remember they had previously recalled an item if that item had been cued in a qualitatively different way on two recall occasions: the “forgot-it-all-along” (FIA) effect. Experiment 1 was designed to determine if the FIA effect arises because participants incorrectly believe they have not been previously tested for an item, or because they incorrectly believe they have failed to recall the item when previously tested. Experiment 2 measured participants' confidence in their incorrect prior-recall judgements, and Experiment 3 tested participants' ability to “recover” their previous recollection when the prior-recall context was restored. Results indicated that participants usually believed they had not previously been cued for the items they failed to remember previously recalling; they were often confident in their incorrect judgements of prior non-remembering; and re-introducing the context of prior remembering sometimes enabled them to recapture their memories of previous recall.     

Eliciting and comparing false and recovered memories: an experimental approach

We describe an experimental paradigm designed to elicit both recovered and false memories in the laboratory. All participants saw, on a video screen, three critical categorized lists of words mixed in randomly with eighteen filler categorized lists. Those in the blocking condition then had several paper‐and‐pencil tasks that involved only the 18 non‐critical filler lists. An uncued recall test was then given, asking participants to recall all the lists they originally saw on the video screen. Finally, there was a cued recall test that provided category cues for the three critical lists. Substantial memory blocking of critical lists on the uncued test and recovery on the cued recall test was observed in all three experiments. In Experiments 2 and 3, many false and recovered memories were elicited on the cued recall test by including cues for the three critical (forgotten) lists, plus cues for three lists that had never been presented. False memories were distinguishable from truly recovered memories in cued recall by ‘know’ versus ‘remember’ judgements, and by confidence ratings; accurately recovered memories were associated with higher confidence. False and recovered memories could not be discriminated based on recall latency. The results repeatedly show powerful effects of memory blocking and recovery. We also show that recovered and false memories can be elicited within a single experimental procedure, and there may be unique characteristics of each. Although we urge caution in generalizing to false and recovered memories of trauma, we suggest that variations of our comparative memory paradigm may be useful for learning about such phenomena. Copyright © 2003 John Wiley & Sons, Ltd.